Peter F. Hamilton's Salvation series [1] has a similar take, but also provides a possible out: don't live on planets or near stars. In Liu Cixin's books (which

Peter F. Hamilton's Salvation series [1] has a similar take, but also provides a possible out: don't live on planets or near stars. In Liu Cixin's books (which I loved btw, also SPOILERS), the level of technology involves weapons that can destroy solar systems. It seems reasonable that such civilizations could live between the stars. I don't agree that Civilizations need to expand without limit. Even humans, having reached a certain level of comfort, have difficulty reproducing enough to maintain population levels. Conceivably then, civilizations will reach a comfortable size and then stop. Certainly they might be willing to stop when they reach a "boundary". The problems with enemies is that, unless we are of sufficient size, we might bump into an enemy that is, say, twice our size, and therefore can thump us in a war. However, novels by Iain M. Banks [2] and Neal Asher [3] provide insight here (Culture vs Iridans, Polity vs Prador). The issue is not how many weapons you have (W), or even how many weapons you can make (dW/dt), but how fast you can make weapons factories (d2w/dt2) (etc). And ultimately, organics simply have absolutely no chance against AI: in both Culture and Polity, the AI runs the war for humans. On the matter of technological breakout, the entire Lensman series has an underlying theme of the back-and-forth of new weapon vs it's mitigation [5]. Liu makes a good case that such back-and-forth is unrealistic: in the time it takes light to travel from the enemy's star to yours, they might go from poking each other with pointy sticks to fusion bombs, or from fusion bombs to star-killers. But there is a simple mitigation there too: don't hang around stars. Or rather, think of stars as Navies think of islands: nice place to refuel and R&R, but don't put all your ships in one harbor. Ultimately, if survival is the goal, then Salvation or We are Bob [4] are the way to go: expand as much as possible. Just be willing to defer to existing civilizations. [1] https://www.goodreads.com/book/show/34068552-salvation https://www.goodreads.com/book/show/34068552-salvation [2] https://www.goodreads.com/author/show/5807106.Iain_M_Banks https://www.goodreads.com/author/show/5807106.Iain_M_Banks [3] https://www.goodreads.com/author/show/56353.Neal_Asher https://www.goodreads.com/author/show/56353.Neal_Asher [4] https://www.amazon.com/Are-Legion-Bob-Bobiverse-Book-ebook/dp/B01LWAESYQ https://www.amazon.com/Are-Legion-Bob-Bobiverse-Book-ebook/d... [5] https://www.goodreads.com/series/49225-lensman https://www.goodreads.com/series/49225-lensman